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Priming Ejectors for priming of Ballast Pumps

Ballast tanks are integral part of large ships. The Ballast tanks are periodically filled and emptied in order to maintain the Ships’s stability and draft.
The process of filling the Ballast Tanks is known as ballasting while the emptying process is known as De-Ballasting. Large ships use a combination of Ballast Pumps and Ballast Eductors to perform the Ballasting & De-Ballasting operations.

Ballast Pumps are typical large capacity Centrifugal Pumps and require the suction line and pump casing to be full of water before start-up.

Depending upon the ship’s draft and level of water in the ballast tanks, it is possible that the level of water may drop below the ballast pump elevation. In such cases the suction pipeline and the pump casing needs to be filled up with water before operation. The process of filling the suction line and pump casing is known as priming.
Priming is an essential operation during start-up of Ballast Pumps.

Priming Ejectors are simple devices that operate on the basis of the jet Venturi principle.
Priming Ejectors utilize the energy in compressed air for their operation and create vacuum at its suction inlet.

The suction inlet of the Priming Ejector is connected to the Suction Pipeline and Ballast Pump casing. This enables the Priming Ejector to evacuate the air inside the Suction Pipeline and draw water upto the pump level.

Priming Ejectors are best suited for priming of Ballast Pumps due to their inherent characteristics
• Ease of Operation – The ejector is switched On/Off entirely by controlling the Air / flow to the ejector. Hence it is not necessary to access the ejector for controlling its operation.
• Priming Ejectors do not contain any moving parts and have large internal passage areas, hence are not vulnerable to liquid entry or clogging by solid particles.
• As they have no moving parts, maintenance requirements are very less. Also it reduces largely the risk of abrupt breakdowns, helps in maintaining the regular production schedule
• Compressed air is a commonly available utility and hence no additional infrastructure is typically required.